Attempt to fix race in GN auto-roller again.
Attempt to fix race in GN auto-roller again.

My previous fix was just wrong and was not correctly checking
whether we had received results from all 3 bots.

R=brettw@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1363703003

Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#350271}

axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk,axinging/chromium-crosswalk